In my recent post, I discussed the bore of an instrument. In brass instruments, the bore of an instrument can be described simply as the diameter of the piping. For example, the trumpet is cylindrical bore instrument. The fact that the diameter of the tubing neither increases nor decreases until it reaches the bell gives the instrument what is perceived by the human ear as a harsher and brighter sound.
A conical instrument’s tubing gradually increases in diameter up to the bell. This creates what is perceived by the human ear as a mellower sound and can be found in cornets, flugelhorns, and other instruments not related to the trumpet.
Another instrument very similar to the trumpet is the flugelhorn. Originally from Germany, the flugelhorn resembles a trumpet with its valves, bell, mouthpiece and slides, but it more conical and has a wider bore, giving it a darker sound. The flugelhorn easy for trumpet players to switch to, as its length is the same as the trumpet, making it a Bb instrument with the same key series as the common Bb trumpet. In pieces where the range of a trumpet is required, but the composer would prefer a less strident sound, the flugelhorn often replaces the trumpet or is added in as a separate part altogether.
The cornet is a sort of middle point between the trumpet and the flugelhorn. Its bore is entirely conical, which accounts for the mellow sound as opposed to the cylindrical-bored, which has a more penetrating sound. The cornet is most commonly used in European brass bands and concert bands. Its use in jazz has declined in favor of the trumpet.